AntiThrombotic Therapy to Ameliorate Clinical Complications in Community Acquired Pneumonia

Recruitment Status
RECRUITING
(See Contacts and Locations)Verified March 2026 by University of Manitoba
Sponsor
University of Manitoba
Information Provided by (Responsible Party)
University of Manitoba
Clinicaltrials.gov Identifier
NCT05848713
Other Study ID Numbers:
ATTACC-CAP
First Submitted
April 16, 2023
First Posted
May 7, 2023
Last Update Posted
April 20, 2026
Last Verified
March 2026

ClinicalTrials.gov processed this data on April 2026. Link to the current ClinicalTrials.gov record .

History of Changes

Study Details

Study Description

The global incidence of hospitalization due to CAP is high and associated with substantive morbidity and mortality. Thrombotic complications - including venous, arterial, and possibly microvascular - occur commonly in hospitalized patients across many etiologies of CAP. Poor outcomes may be mediated by both inflammatory and thrombotic processes leading to respiratory, cardiac, and other end organ dysfunction. There are currently no established therapies that modify the potentially maladaptive immunothrombosis pathway in CAP.

Therapeutic-dose anticoagulation with heparin reduces disease progression and mortality in non-critically ill patients hospitalized with COVID-19 with an acceptable safety profile. COVID-19 shares pathogenic features, including activation of the inflammatory and coagulation cascades, with other pneumonias. Whether therapeutic-dose heparin confers similar clinical benefits in non-COVID-19 CAP is unknown.

Condition or DiseaseIntervention/Treatment
Community-acquired Pneumonia
Drug: Heparin

Study Design

Study TypeInterventional
Actual Enrollment4000 participants
Design AllocationRandomized
Interventional ModelParallel Assignment
MaskingNone (Open Label)
Primary PurposeTreatment
Official TitleAntiThrombotic Therapy to Ameliorate Clinical Complications in Community Acquired Pneumonia
Study Start DateOctober 9, 2023
Actual Primary Completion Date1yr 10mos from now
Actual Study Completion Date2yrs 10mos from now

Groups and Cohorts

Group/CohortIntervention/Treatment
Therapeutic-Dose Heparin
Participants randomized to the investigational arm will receive a pragmatic strategy of therapeutic-dose low molecular-weight heparin (LMWH) or unfractionated heparin (UFH) administered daily for up to 14 days or until hospital discharge, whichever occurs first. Participants should start receiving study drug as soon as possible following randomization.
Drug: Heparin
Preference is for LMWH given ease of administration and possibility of a more favorable safety profile, if no contraindication is present. Enoxaparin, dalteparin, or tinzaparin are acceptable LMWHs to be used for patients in the investigational arm and dose should be based on measured or estimated weight of the patient. Alternatively, intravenous UFH may be used and may be preferred in the presence of significant renal compromise. Intravenous UFH is typically dosed according to total body weight and pragmatically adjusted according to local institutional policy to achieve an activated partial thromboplastin time (aPTT) of 1.5-2.5x the reference value, or a corresponding UFH anti-Xa level. If UFH is used, the availability of a local site policy that specifies an aPTT target in this range or a corresponding anti-Xa value is a requirement.
Usual Care
Participants randomized to the control arm will receive usual care thromboprophylactic dose anticoagulation according to local practice. To ensure adequate separation between the study groups, the dose of heparin/LMWH used in the usual care arm should not equal more than half of the approved therapeutic dose for that agent according to local VTE treatment protocols.

Outcome Measures

Primary Outcome Measures
  1. Ordinal endpoint reflecting survival
    Survival to hospital discharge without ICU-level organ support. Organ support is defined as receipt of high flow nasal oxygen, invasive or non-invasive mechanical ventilation, vasopressor/inotropic therapy, or extracorporeal life support (ECLS) within an ICU. This outcome reflects disease progression to ICU-level organ failure or the worst possible outcome (death). It was chosen because of its importance to patients, clinicians, and other stakeholders. Given the limited number of ICU beds, reducing the burden of critical illness has important health system capacity implications.
Secondary Outcome Measures
  1. Bleeding events
    Number of participants with major bleeds as defined by the ISTH definition.
  2. HIT events
    Number of participants with laboratory confirmed heparin induced thrombocytopenia (HIT)
  3. Thrombotic events
    Number of participants with deep vein thrombosis, pulmonary embolism, systemic arterial thromboembolism, myocardial infarction, or ischemic stroke
  4. Invasive mechanical ventilation
    Ordered categorical endpoint with three possible outcomes based on the worst status of each patient through day 30 following randomization
  5. All cause mortality
  6. Hospital-free days
    Days alive outside hospital
  7. Health related quality of life
    Using the EQ-5D-5L instrument
  8. Health related quality of life
    Using the Clinical Frailty Scale instrument

Eligibility Criteria

Ages Eligible for Study(Adult, Older Adult)
Sexes Eligible for StudyAll
Accepts Healthy VolunteersNo
Inclusion Criteria
1. Patients ≥18 years of age 2. Admitted to hospital for a suspected or confirmed diagnosis of CAP defined by: 1. Radiographic evidence of new or worsening infiltrate 2. One or more of the following signs and/or symptoms of lower respiratory tract infection i. New or increased cough or sputum production ii. Fever of \> 37.8C or temperature \< 36C iii. WBC \> 11 x 109/L or \< 4 x 109/L c. The primary diagnosis is believed to be CAP as per the attending physician 3. Requires supplemental oxygen to treat hypoxemia (or requires an increased level of supplemental oxygen if on chronic oxygen therapy) 4. Hospital admission anticipated to last ≥72 hours from randomization
Exclusion Criteria
1. Suspected or confirmed active COVID-19 infection 2. Hospital admission for \>72 hours prior to randomization 3. Patients receiving non-invasive or invasive ventilation, vasopressors, or extracorporeal life support (ECLS) within an ICU at the time of enrollment 4. Requirement for chronic mechanical ventilation via tracheostomy prior to hospitalization 5. Patients for whom the intent is to not use pharmacologic thromboprophylaxis 6. Patients with an independent indication for therapeutic-dose anticoagulation 7. Patients with a contraindication to therapeutic-dose anticoagulation, including: 1. Non-traumatic bleeding that requires medical evaluation or hospitalization within 30 days prior to CAP hospital admission 2. History of an inherited or acquired bleeding disorder 3. Cerebral aneurysm or mass lesions of the central nervous system 4. Ischemic stroke within 3 months of hospital admission 5. Gastrointestinal bleeding within 3 months of hospital admission 6. Platelet count \<50 x109/L OR INR \>2.0 OR hemoglobin \<80 g/L at the time of screening 7. Other physician-perceived contraindications to therapeutic anticoagulation 8. History of heparin induced thrombocytopenia (HIT) or other heparin allergy 9. Current or recent (within 7 days of screening) use of dual anti-platelet inhibitors (For example; Aspirin + one of the following; clopidogrel, ticagrelor, prasugrel) 10. Patients in whom imminent death is anticipated 11. Anticipated transfer to another hospital that is not a study site within 72 hours of randomization 12. Enrollment in other interventional trials related to anticoagulation or antiplatelet therapy during current hospitalization

Contacts and Locations

Sponsors and CollaboratorsUniversity of Manitoba
Locations
University of Chicago | Chicago Illinois, United States, 60637Ochsner Clinic | Jefferson Louisiana, United States, 70121Maine Medical Centre | Portland Maine, United States, 04102Henry Ford Health System | Dearborn Michigan, United States, 48128Cooper University Health Care | Camden New Jersey, United States, 08103Medical College of Wisconsin | Milwaukee Wisconsin, United States, 53226Hospital Estadual Dr. Jayme Santos Neves | Serra Espírito Santo, Brazil, 29166-828Hospital Evangelico de Vila Velha | Vila Velha Espírito Santo, Brazil, Hospital Universitário Cassiano Antonio Moraes | Vitória Espírito Santo, Brazil, Santa Casa de Misericordia de Itabuna | Itabuna Estado de Bahia, Brazil, Hospital Brasilia | Brasília Federal District, Brazil, Hospital Sao Brasilia | Brasília Federal District, Brazil, Instituto de Cardiologia e Transplantes do Distrito Federal | Brasília Federal District, Brazil, Hospital de Messejana Dr. Carlos Alberto Studart Gomes | Goiânia Goiás, Brazil, Hospital Ruy Azeredo | Goiânia Goiás, Brazil, Instituto Goiano de Oncologia e Hematologia - INGOH | Goiânia Goiás, Brazil, Hospital Felicio Rocho | Belo Horizonte Minas Gerais, Brazil, NUPEC-Orizonti | Belo Horizonte Minas Gerais, Brazil, Hospital do Rocio | Campo Largo Paraná, Brazil, 83606-177Hospital Santa Cruz | Curitiba Paraná, Brazil, PUCPR | Curitiba Paraná, Brazil, Hospital Bruno Born | Lajeado Rio Grande do Sul, Brazil, Hospital Sao Vicente de Paulo | Passo Fundo Rio Grande do Sul, Brazil, Hospital de Clínicas de Porto Alegre | Porto Alegre Rio Grande do Sul, Brazil, Hospital Universitario de Santa Maria | Santa Maria Rio Grande do Sul, Brazil, Hospital Sao Jose | Criciúma Santa Catarina, Brazil, Hospital Regional Homero Miranda Gomes | São José South Carolina, Brazil, Hospital de Reabilitacao de Anomalias Craniofaciais | Bauru São Paulo, Brazil, UPECLIN - Unidade de Pesquisa Clínica da Faculdade de Medicina de Botucatu | Botucatu São Paulo, Brazil, Hospital Universitario Sao Francisco na Providencia na Deus | Bragança Paulista São Paulo, Brazil, Fundação Centro Médico de Campinas | Campinas São Paulo, Brazil, 13083-190IPECC | Campinas São Paulo, Brazil, CiTen - Centro Hospital Municipal Antonio Giglio | Osasco São Paulo, Brazil, Hospital Regional de Presidente Prudente | Presidente Prudente São Paulo, Brazil, Hospital Estadual de Serrana | Ribeirão Preto São Paulo, Brazil, Hospital Nipo-Brasileiro | São Paulo São Paulo, Brazil, 02189-010HCFMUSP | São Paulo São Paulo, Brazil, 05403-010Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo | São Paulo São Paulo, Brazil, Santa Casa de Misericordia de Sao Paulo | São Paulo São Paulo, Brazil, Foothills Medical Centre | Calgary Alberta, Canada, T2N 2T9Grand Prairie Regional Hospital | Grande Prairie Alberta, Canada, T8V 4B1Nanaimo Regional General Hospital | Nanaimo British Columbia, Canada, Vancouver General Hospital | Vancouver British Columbia, Canada, V5Z 1M9Health Sciences Center Winnipeg | Winnipeg Manitoba, Canada, R3A 1R9Grace General Hospital | Winnipeg Manitoba, Canada, St. Boniface General Hospital | Winnipeg Manitoba, Canada, Memorial University | St. John's Newfoundland and Labrador, Canada, A1C 5S7Health Sciences North Research Institute | Greater Sudbury Ontario, Canada, P3E 2H3Hamilton Health Sciences - Juravinski | Hamilton Ontario, Canada, Hamilton Health Sciences | Hamilton Ontario, Canada, Markham Stouffville Hospital | Markham Ontario, Canada, L3P 7P3Hôpital Montfort | Ottawa Ontario, Canada, The Ottawa Hospital | Ottawa Ontario, Canada, Niagara Health System - St Catharines Site | Saint Catherines Ontario, Canada, L2S 0A9Sunnybrook Health Sciences Centre | Toronto Ontario, Canada, M4N 3M5University Health Network | Toronto Ontario, Canada, M5G2C4Centre Hospitalier de Quebec - Hotel-Dieu de Levis | Lévis Quebec, Canada, G6V 3Z1McGill University Health Centre | Montreal Quebec, Canada, H4A3J1Centre Hospitalier de l'université de Montréal (CHUM) | Montreal Quebec, Canada, Jewish General Hospital | Montreal Quebec, Canada, CHU de Quebec-University Laval | Québec Quebec, Canada, Institut universitaire de cardiologie et de pneumologie de Québec (IUCPQ) | Québec Quebec, Canada, Centre Hospitalier Universitaire de Sherbrooke | Sherbrooke Quebec, Canada, Regina General Hospital | Regina Saskatchewan, Canada, S4P 0W5
Investigators
Principal Investigator: Ryan Zarychanski, MD, University of ManitobaPrincipal Investigator: Patrick Lawler, MD, University Health Network and McGill UniversityPrincipal Investigator: Sylvain Lother, MD, University of ManitobaPrincipal Investigator: Alexis Turgeon, MD, L'Universite Laval